Method and apparatus for catheter-based annuloplasty using local plications

ABSTRACT

The present invention relates to a minimally invasive method of performing annuloplasty. According to one aspect of the present invention, a method for performing annuloplasty includes accessing a left ventricle of a heart to provide a discrete plication element to the left ventricle, and engaging the plication element to tissue near a mitral valve of the heart. Engaging the plication element includes causing the plication element to gather a portion of the tissue to create a plication. In one embodiment, accessing the left ventricle of the heart to provide the plication element includes accessing the left ventricle of the heart using a catheter arrangement.

CROSS REFERENCE TO RELATED APPLICATION

[0001] The present invention is a Continuation-in-Part of co-pendingU.S. patent application Ser. No. 09/841,968, entitled “Method andApparatus for Catheter-Based Annuloplasty,” filed Apr. 24, 2001, whichis incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

[0002] 1. Field of Invention

[0003] The present invention relates generally to techniques fortreating mitral valve insufficiencies such as mitral valve leakage. Moreparticularly, the present invention relates to systems and methods fortreating a leaking mitral valve in a minimally invasive manner.

[0004] 2. Description of the Related Art

[0005] Congestive heart failure (CHF), which is often associated with anenlargement of the heart, is a leading cause of death. As a result, themarket for the treatment of CHF is becoming increasingly prevalent. Forinstance, the treatment of CHF is a leading expenditure of Medicare andMedicaid dollars in the United States of America. Typically, thetreatment of CHF enables many who suffer from CHF to enjoy an improvedquality of life.

[0006] Referring initially to FIG. 1, the anatomy of a heart,specifically the left side of a heart, will be described. The left sideof a heart 104 includes a left atrium 108 and a left ventricle 112. Anaorta 114 receives blood from left ventricle 112 through an aortic valve120, which serves to prevent regurgitation of blood back into leftventricle 112. A mitral valve 116 is disposed between left atrium 108and left ventricle 112, and effectively controls the flow of bloodbetween left atrium 108 and left ventricle 112.

[0007] Mitral valve 116, which will be described below in more detailwith respect to FIG. 2a, includes an anterior leaflet and a posteriorleaflet that are coupled to cordae tendonae 124 which serve as “tensionmembers” that prevent the leaflets of mitral valve 116 from openingindiscriminately. When left ventricle 112 contracts, cordae tendonae 124allow the anterior leaflet to open upwards until limited in motion bycordae tendonae 124. Normally, the upward limit of opening correspondsto a meeting of the anterior and posterior leaflets and the preventionof backflow. Cordae tendonae 124 arise from a columnae carnae 128 or,more specifically, a musculi papillares of columnae carnae 128.

[0008] Left ventricle 112 includes trabeculae 132 which are fibrouscords of connective tissue that are attached to wall 134 of leftventricle 112. Trabeculae 132 are also attached to an interventricularseptum 136 which separates left ventricle 112 from a right ventricle(not shown) of heart 104. Trabeculae 132 are generally located in leftventricle 112 below columnae carnae 128.

[0009]FIG. 2a is a cut-away top-view representation of mitral valve 116and aortic valve 120. Aortic valve 120 has a valve wall 204 that issurrounded by a skeleton 208 a of fibrous material. Skeleton 208 a maygenerally be considered to be a fibrous structure that effectively formsa ring around aortic valve 120. A fibrous ring 208 b, which issubstantially the same type of structure as skeleton 208 a, extendsaround mitral valve 116. Mitral valve 116 includes an anterior leaflet212 and a posterior leaflet 216, as discussed above. Anterior leaflet212 and posterior leaflet 216 are generally thin, flexible membranes.When mitral valve 116 is closed (as shown in FIG. 2a), anterior leaflet212 and posterior leaflet 216 are generally aligned and contact oneanother to create a seal. Alternatively, when mitral valve 116 isopened, blood may flow through an opening created between anteriorleaflet 212 and posterior leaflet 216.

[0010] Many problems relating to mitral valve 116 may occur and theseinsufficiencies may cause many types of ailments. Such problems include,but are not limited to, mitral regurgitation. Mitral regurgitation, orleakage, is the backflow of blood from left ventricle 112 into the leftatrium 108 due to an imperfect closure of mitral valve 116. That is,leakage often occurs when a gap is created between anterior leaflet 212and posterior leaflet 216.

[0011] In general, a relatively significant gap may exist betweenanterior leaflet 212 and posterior leaflet 216 (as shown in FIG. 2b) fora variety of different reasons. For example, a gap may exist due tocongenital malformations, because of ischemic disease, or because aheart has been damaged by a previous heart attack. A gap may also becreated when congestive heart failure, e.g., cardiomyopathy, or someother type of distress causes a heart to be enlarged. When a heart isenlarged, the walls of the heart, e.g., wall 134 of a left ventricle,may stretch or dilate, causing posterior leaflet 216 to stretch. Itshould be appreciated that anterior leaflet 212 generally does notstretch. As shown in FIG. 2b, a gap 220 between anterior leaflet 212 andstretched posterior leaflet 216′ is created when wall 134′ stretches.Hence, due to the existence of gap 220, mitral valve 116 is unable toclose properly, and may begin to leak.

[0012] Leakage through mitral valve 116 generally causes a heart tooperate less efficiently, as the heart must work harder to maintain aproper amount of blood flow therethrough. Leakage through mitral valve116, or general mitral insufficiency, is often considered to be aprecursor to CHF. There are generally different levels of symptomsassociated with heart failure. Such levels are classified by the NewYork Heart Association (NYHA) functional classification system. Thelevels range from a Class 1 level which is associated with anasymptomatic patient who has substantially no physical limitations to aClass 4 level which is associated with a patient who is unable to carryout any physical activity without discomfort, and has symptoms ofcardiac insufficiency even at rest. In general, correcting for mitralvalve leakage may be successful in allowing the NYHA classificationgrade of a patient to be reduced. For instance, a patient with a Class 4classification may have his classification reduced to Class 3 and,hence, be relatively comfortable at rest.

[0013] Treatments used to correct for mitral valve leakage or, moregenerally, CHF, are typically highly invasive, open-heart surgicalprocedures. Ventricular assist devices such as artificial hearts may beimplanted in a patient whose own heart is failing. The implantation of aventricular assist device is often expensive, and a patient with aventricular assist device must be placed on extended anti-coagulanttherapy. As will be appreciated by those skilled in the art,anti-coagulant therapy reduces the risk of blood clots being formed, asfor example, within the ventricular assist device. While reducing therisks of blood clots associated with the ventricular assist device isdesirable, anti-coagulant therapies may increase the risk ofuncontrollable bleeding in a patient, e.g., as a result of a fall, whichis not desirable.

[0014] Rather than implanting a ventricular assist device,bi-ventricular pacing devices similar to pace makers may be implanted insome cases, e.g., cases in which a heart beats inefficiently in aparticular asynchronous manner. While the implantation of abi-ventricular pacing device may be effective, not all heart patientsare suitable for receiving a bi-ventricular pacing device. Further, theimplantation of a bi-ventricular pacing device is expensive.

[0015] Open-heart surgical procedures which are intended to correct formitral valve leakage, specifically, involve the implantation ofreplacement valves. Valves from animals, e.g., pigs, may be used toreplace a mitral valve 116 in a human. While the use of a pig valve mayrelatively successfully replace a mitral valve, such valves generallywear out, thereby requiring additional open surgery at a later date.Mechanical valves, which are less likely to wear out, may also be usedto replace a leaking mitral valve. However, when a mechanical valve isimplanted, there is an increased risk of thromboembolism, and a patientis generally required to undergo extended anti-coagulant therapies.

[0016] A less invasive surgical procedure involves heart bypass surgeryassociated with a port access procedure. For a port access procedure,the heart may be accessed by cutting a few ribs, as opposed to openingthe entire chest of a patient. In other words, a few ribs may be cut ina port access procedure, rather than opening a patient's sternum.

[0017] One open-heart surgical procedure that is particularly successfulin correcting for mitral valve leakage and, in addition, mitralregurgitation, is an annuloplasty procedure. During an annuloplastyprocedure, an annuloplasty ring may be implanted on the mitral valve tocause the size of a stretched mitral valve 116 to be reduced to arelatively normal size. FIG. 3 is a schematic representation of anannuloplasty ring. An annuloplasty ring 304 is shaped approximately likethe contour of a normal mitral valve. That is, annuloplasty ring 304 isshaped substantially like the letter “D.” Typically, annuloplasty ring304 may be formed from a rod or tube of biocompatible material, e.g.,plastic, that has a DACRON mesh covering.

[0018] In order for annuloplasty ring 304 to be implanted, a surgeonsurgically attaches annuloplasty ring 304 to the mitral valve on theatrial side of the mitral valve. Conventional methods for installingring 304 require open-heart surgery which involve opening a patient'ssternum and placing the patient on a heart bypass machine. As shown inFIG. 4, annuloplasty ring 304 is sewn to a posterior leaflet 318 and ananterior leaflet 320 of a top portion of mitral valve 316. In sewingannuloplasty ring 304 onto mitral valve 316, a surgeon generallyalternately acquires a relatively large amount of tissue from mitraltissue, e.g., a one-eighth inch bite of tissue, using a needle andthread, followed by a smaller bite from annuloplasty ring 304. Once athread has loosely coupled annuloplasty ring 304 to mitral valve tissue,annuloplasty ring 304 is slid onto mitral valve 316 such that tissuethat was previously stretched out, e.g., due to an enlarged heart, iseffectively pulled in using tension applied by annuloplasty ring 304 andthe thread which binds annuloplasty ring 304 to the mitral valve tissue.As a result, a gap, such as gap 220 of FIG. 2b, between anterior leaflet320 and posterior leaflet 318 may be substantially closed off. After themitral valve is shaped by ring 304, the anterior and posterior leaflets320, 318 will reform to create a new contact line and will enable mitralvalve 318 to appear and to function as a normal mitral valve.

[0019] Once implanted, tissue generally grows over annuloplasty ring304, and a line of contact between annuloplasty ring 304 and mitralvalve 316 will essentially enable mitral valve 316 to appear andfunction as a normal mitral valve. Although a patient who receivesannuloplasty ring 304 may be subjected to anti-coagulant therapies, thetherapies are not extensive, as a patient is only subjected to thetherapies for a matter of weeks, e.g., until tissue grows overannuloplasty ring 304.

[0020] A second surgical procedure which is generally effective inreducing mitral valve leakage involves placing a single edge-to-edgesuture in the mitral valve. With reference to FIG. 5a, such a surgicalprocedure, e.g., an Alfieri stitch procedure or a bow-tie repairprocedure, will be described. An edge-to-edge stitch 404 is used tostitch together an area at approximately the center of a gap 408 definedbetween an anterior leaflet 420 and a posterior leaflet 418 of a mitralvalve 416. Once stitch 404 is in place, stitch 404 is pulled in to forma suture which holds anterior leaflet 420 against posterior leaflet 418,as shown. By reducing the size of gap 408, the amount of leakage throughmitral valve 416 may be substantially reduced.

[0021] Although the placement of edge-to-edge stitch 404 is generallysuccessful in reducing the amount of mitral valve leakage through gap408, edge-to-edge stitch 404 is conventionally made through open-heartsurgery. In addition, the use of edge-to-edge stitch 404 is generallynot suitable for a patient with an enlarged, dilated heart, as bloodpressure causes the heart to dilate outward, and may put a relativelylarge amount of stress on edge-to-edge stitch 404. For instance, bloodpressure of approximately 120/80 or higher is typically sufficient tocause the heart to dilate outward to the extent that edge-to-edge stitch404 may become undone, or tear mitral valve tissue.

[0022] Another surgical procedure which reduces mitral valve leakageinvolves placing sutures along a mitral valve annulus around theposterior leaflet. A surgical procedure which places sutures along amitral valve with be described with respect to FIG. 5b. Sutures 504 areformed along an annulus 540 of a mitral valve 516 around a posteriorleaflet 518 of mitral valve 516, and may be formed as a double track,e.g., in two “rows,” from a single strand of suture material. Sutures504 are tied off at approximately a central point 506 of posteriorleaflet 518. Pledgets 546 are often positioned under selected sutures504, e.g., at central point 506, to prevent sutures 504 from tearingthrough annulus 540. When sutures 504 are tied off, annulus 540 mayeffectively be tightened to a desired size such that the size of a gap508 between posterior leaflet 518 and an anterior leaflet 520 may bereduced.

[0023] The placement of sutures 504 along annulus 540, in addition tothe tightening of sutures 504, is generally successful in reducingmitral valve leakage. However, the placement of sutures 504 isconventionally accomplished through open-heart surgical procedures. Thatis, like other conventional procedures, a suture-based annuloplastyprocedure is invasive.

[0024] While invasive surgical procedures have proven to be effective inthe treatment of mitral valve leakage, invasive surgical proceduresoften have significant drawbacks. Any time a patient undergoesopen-heart surgery, there is a risk of infection. Opening the sternumand using a cardiopulmonary bypass machine has also been shown to resultin a significant incidence of both short and long term neurologicaldeficits. Further, given the complexity of open-heart surgery, and thesignificant associated recovery time, people who are not greatlyinconvenienced by CHF symptoms, e.g., people at a Class 1classification, may choose not to have corrective surgery. In addition,people who most need open heart surgery, e.g., people at a Class 4classification, may either be too frail or too weak to undergo thesurgery. Hence, many people who may benefit from a surgically repairedmitral valve may not undergo surgery.

[0025] Therefore, what is needed is a minimally invasive treatment formitral valve leakage. Specifically, what is desired is a method forreducing leakage between an anterior leaflet and a posterior leaflet ofa mitral valve that does not require conventional surgical intervention.

SUMMARY OF THE INVENTION

[0026] The present invention relates to a non-invasive method ofperforming annuloplasty. According to one aspect of the presentinvention, a method for performing annuloplasty includes accessing aleft ventricle of a heart to provide a discrete plication element to theleft ventricle, and engaging the plication element to tissue near amitral valve of the heart. Engaging the plication element includescausing the plication element to gather a portion of the tissue tocreate a plication. In one embodiment, accessing the left ventricle ofthe heart to provide the plication element includes accessing the leftventricle of the heart using a catheter arrangement.

[0027] In another embodiment, engaging the plication element to tissuenear the mitral valve includes piercing the tissue using the plicationelement, which causes a first portion of the plication element to bepositioned on an atrial side of the mitral valve and a second portion ofthe plication element to be positioned on a ventricular side of themitral valve. In such an embodiment, a delivery catheter may beconfigured to cause the first portion of the plication element to bepositioned on the atrial side of the mitral valve.

[0028] Performing an annuloplasty on a mitral valve by accessing theleft ventricle of the heart, as for example using a catheter, enablescomplicated surgical procedures to be avoided when treating mitral valveleakage. Avoiding open-heart surgical procedures generally makesannuloplasty more accessible to patients who may benefit fromannuloplasty. As mitral valve leakage is often considered to be an earlyindicator of congestive heart failure, a minimally invasive annuloplastyprocedure that corrects for leakage problems, such as one which involvespositioning discrete plications in fibrous tissue around the mitralvalve, may greatly improve the quality of life of many patients whomight not be suitable for invasive annuloplasty procedures.

[0029] According to another aspect of the present invention, a methodfor performing an annuloplasty includes accessing tissue located nearthe mitral valve of a heart, and creating a first discrete plication inthe tissue using a first plication element. The first discrete plicationcauses an arc length of the mitral valve to be reduced by effectivelyshrinking the size of the annulus around the mitral valve. In oneembodiment, accessing the tissue includes accessing the tissue through aleft ventricle of the heart using a catheter. In such an embodiment, thefirst plication element may be provided through the catheter.

[0030] In other embodiments, the first plication element may be a clipelement, a locking element, or an element that includes bar pieces, athread, and a lock. The thread may generally be a tension element, aflexible tension element, or a suture. Creating the first discreteplication in the tissue using a clip element includes engaging thetissue using the clip element. When the first plication element is alocking element, such as a locking element that includes two pieces,creating the first discrete plication includes penetrating the tissueusing a part of the first piece and a part of the second piece, andengaging the tissue between the first piece and the second piece.Alternatively, when the first plication element includes bar pieces, athread, and a lock, creating the first discrete plication includespenetrating the tissue to position the bar pieces on an atrial side ofthe tissue, tensioning the thread to position the bar pieces against theatrial side of the tissue, and locking the lock against a ventricularside of the tissue to create the first discrete plication between thebar pieces and the lock.

[0031] According to still another aspect of the present invention, asystem that is suitable use in an annuloplasty procedure includes acatheter assembly and a bendable member. The catheter assembly isconfigured for insertion through an aorta of the heart into a leftventricle of the heart to reach a region of the left ventriclesubstantially below the mitral valve, and the bendable member is movablebetween a first position for insertion into a left ventricle through thecatheter assembly and a second position. The bendable member is alsoconfigured to create a plication in tissue near a mitral valve when itis in the second position.

[0032] According to yet another aspect of the present invention, asystem that is suitable for use in an annuloplasty procedure includes acatheter assembly and a suture structure. The catheter assembly isconfigured for insertion through an aorta of the heart into a leftventricle of the heart to reach a region of the left ventriclesubstantially below the mitral valve. The suture structure includes afirst bar member, a second bar member, a thread, and a lock element thatmoves or slides over the thread. The catheter assembly is furtherconfigured to cause the first bar member and the second bar member topenetrate tissue near the mitral valve, and to move the lock elementover the thread into contact with the tissue on a ventricular side ofthe mitral valve. A plication is created in the tissue substantiallybetween the first bar member, the second bar member, and the lockelement.

[0033] In accordance with another aspect of the present invention, asystem for performing annuloplasty on a mitral valve of a heart includesa catheter assembly, a guide element, and a plication element. Thecatheter assembly is configured for insertion through an aorta of theheart into a left ventricle of the heart to reach a region of the leftventricle substantially below the mitral valve. The guide element isshaped for insertion into the catheter assembly, and the plicationelement is shaped for insertion over the guide element using thecatheter assembly into the left ventricle substantially below the mitralvalve. The plication element is configured to gather tissue of the heartto create a plication in the tissue.

[0034] These and other advantages of the present invention will becomeapparent upon reading the following detailed descriptions and studyingthe various figures of the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The invention may best be understood by reference to thefollowing description taken in conjunction with the accompanyingdrawings in which:

[0036]FIG. 1 is a cross-sectional front-view representation of the leftside of a human heart.

[0037]FIG. 2a is a cut-away top-view representation of the mitral valveand the aortic valve of FIG. 1.

[0038]FIG. 2b is a cut-away representation of a stretched mitral valveand an aortic valve.

[0039]FIG. 3 is a representation of an annular ring that is suitable foruse in performing a conventional annuloplasty procedure.

[0040]FIG. 4 is a representation of a mitral valve and an aortic valveafter the annular ring of FIG. 3 has been implanted.

[0041]FIG. 5a is a representation of a mitral valve and an aortic valveafter a single edge-to-edge suture has been applied to reduce mitralregurgitation.

[0042]FIG. 5b is a representation of a mitral valve and an aortic valveafter sutures along a mitral valve annulus have been applied to reducemitral regurgitation.

[0043]FIG. 6a is a representation of a delivery tube and a J-catheter inaccordance with an embodiment of the present invention.

[0044]FIG. 6b is a cut-away front view of the left side of a heart inwhich the delivery tube and the J-catheter of FIG. 6a have been insertedin accordance with an embodiment of the present invention.

[0045]FIG. 7a is a representation of a catheter assembly in accordancewith an embodiment of the present invention.

[0046]FIG. 7b is a cross-sectional representation of the catheterassembly of FIG. 7a in accordance with an embodiment of the presentinvention.

[0047]FIG. 7c is a cut-away top-view representation of a left ventriclein which the gutter catheter of FIGS. 7a and 7 b has been positioned inaccordance with an embodiment of the present invention.

[0048]FIG. 8 is a cut-away top-view representation of a left ventriclein which a guide wire has been positioned in accordance with anembodiment of the present invention.

[0049]FIG. 9a is a cut-away top-view representation of a left ventricleof the heart in which local plication suture structures have beenimplanted in accordance with an embodiment of the present invention.

[0050]FIG. 9b is a cut-away top-view representation of a left ventricleof the heart in which local plication suture structures which arecoupled have been implanted in accordance with an embodiment of thepresent invention.

[0051]FIG. 10a is a representation of a suture structure after T-barshave been introduced to an atrial side of a mitral valve through fibroustissue near the mitral valve in accordance with an embodiment of thepresent invention.

[0052]FIG. 10b is a representation of the suture structure of FIG. 10aafter the T-bars have been engaged to the fibrous tissue in accordancewith an embodiment of the present invention.

[0053]FIG. 11 is a representation of a suture structure which includes alocking element with a spring in accordance with an embodiment of thepresent invention.

[0054]FIG. 12a is a representation of a suture structure which includesa locking element with a resorbable component in accordance with anembodiment of the present invention.

[0055]FIG. 12b is a representation of the suture structure of FIG. 12aafter the resorbable component has degraded in accordance with anembodiment of the present invention.

[0056]FIG. 12c is a representation of the suture structure of FIG. 12bafter a plication has been created in accordance with an embodiment ofthe present invention.

[0057]FIG. 13a is a representation of a first catheter which is suitablefor use in delivering and implementing a suture structure in accordancewith an embodiment of the present invention.

[0058]FIG. 13b is a representation of a second catheter which issuitable for use in delivering and implementing a suture structure inaccordance with an embodiment of the present invention.

[0059]FIG. 13c is a representation of a third catheter assembly which issuitable for use in delivering and implementing a suture structure inaccordance with an embodiment of the present invention.

[0060]FIGS. 14a and 14 b are a process flow diagram which illustratesthe steps associated with one method of performing annuloplasty using asuture structure and a catheter in accordance with an embodiment of thepresent invention.

[0061]FIG. 15 is a cut-away top-view representation of a left ventricleof the heart in which local plication elements have been implanted inaccordance with an embodiment of the present invention.

[0062]FIG. 16a is a representation of a local plication element whichhas spring-like characteristics in accordance with an embodiment of thepresent invention.

[0063]FIG. 16b is a representation of the local plication element ofFIG. 16a after forces have been applied to open the local plicationelement in accordance with an embodiment of the present invention.

[0064]FIG. 16c is a representation of the local plication element ofFIG. 16b after tips of the local plication element pierce through tissuein accordance with an embodiment of the present invention.

[0065]FIG. 16d is a representation of the local plication element ofFIG. 16c after the tips of the local plication element engage the tissueto form a local plication in accordance with an embodiment of thepresent invention.

[0066]FIG. 17a is a representation of a local plication element, whichis formed from a shape memory material, in an open state in accordancewith an embodiment of the present invention.

[0067]FIG. 17b is a representation of the local plication element ofFIG. 17a in a closed state in accordance with an embodiment of thepresent invention.

[0068]FIG. 18a is a representation of a first self-locking clip which issuitable for use in forming a local plication in accordance with anembodiment of the present invention.

[0069]FIG. 18b is a representation of a second self-locking clip whichis suitable for use in forming a local plication in accordance with anembodiment of the present invention.

[0070]FIG. 19 is a representation of a plication-creating lockingmechanism in accordance with an embodiment of the present invention.

[0071]FIG. 20a is a representation of the plication-creating lockingmechanism of FIG. 19 as provided within the left ventricle of a heart inaccordance with an embodiment of the present invention.

[0072]FIG. 20b is a representation of the plication-creating lockingmechanism of FIG. 20a after forces have been applied to cause tines ofthe mechanism to contact tissue in accordance with an embodiment of thepresent invention.

[0073]FIG. 20c is a representation of the plication-creating lockingmechanism of FIG. 20b after tissue has been gathered between the tinesof the mechanism in accordance with an embodiment of the presentinvention.

[0074]FIG. 20d is a representation of the plication-creating lockingmechanism of FIG. 20c after a local plication has been formed inaccordance with an embodiment of the present invention.

[0075]FIGS. 21a and 21 b are a process flow diagram which illustratesthe steps associated with one method of performing annuloplasty using alocal plication element and a catheter in accordance with an embodimentof the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0076] Invasive, open-heart surgical procedures are generally effectivein the treatment of mitral valve leakage. However, open-heart surgicalprocedures may be particularly hazardous to some patients, e.g., frailpatients or patients who are considered as being very ill, andundesirable to other patients, e.g., patients who are asymptomatic anddo not wish to undergo a surgical procedure. As such, open-heartsurgical procedures to correct mitral valve leakage or, more generally,mitral valve insufficiency, are not suitable for many patients who wouldlikely benefit from reducing or eliminating the mitral valve leakage.

[0077] A catheter-based annuloplasty procedure enables annuloplasty tobe performed on a patient without requiring that the patient undergoopen-heart surgery, or be placed on cardiopulmonary bypass. Cathetersmay be introduced into the left ventricle of a heart through the aortato position a guide wire and plication implants on the ventricular sideof a mitral valve, i.e., under a mitral valve. Catheters may also beused to couple the plication implants to fibrous tissue associated withthe skeleton of the heart around the mitral valve.

[0078] The use of catheters to perform an annuloplasty procedure bydelivering and engaging plication implants or structures enables theannuloplasty procedure to be performed without open-heart surgery, andwithout a bypass procedure. Recovery time associated with theannuloplasty, as well as the risks associated with annuloplasty, may besubstantially minimized when the annuloplasty is catheter-based. As aresult, annuloplasty becomes a more accessible procedure, since manypatients who might previously not have received treatment for mitralvalve leakage, e.g., frail patients and asymptomatic patients, maychoose to undergo catheter-based annuloplasty.

[0079] To begin a catheter-based annuloplasty procedure, a delivery tubeand a J-catheter may be inserted into a left ventricle of the heartthrough the aorta. Inserting the delivery tube and the J-catheterthrough the aorta enables the left ventricle of the heart to be reachedsubstantially without coming into contact with trabeculae or the cordaetendonae in the left ventricle. FIG. 6a is a diagrammatic representationof a delivery tube and a J-catheter in accordance with an embodiment ofthe present invention. Delivery tube 604 has a substantially circularcross section, and is configured to receive a J-catheter 608. J-catheter608 is arranged to move longitudinally through and opening in deliverytube 604 as needed.

[0080] In general, delivery tube 604 is an elongated body which may beformed from a flexible, durable, biocompatible material such as nylon,urethane, or a blend of nylon and urethane, e.g., PEBAX®. Likewise,J-catheter 608, which is also an elongated body, may also be formed froma biocompatible material. A material used to form J-catheter 608 istypically also relatively flexible. In the described embodiment, a tipof J-catheter 608 is rigid enough to allow the tip of J-catheter 608 tomaintain a relatively curved shape, e.g., a “J” shape. The curve inJ-catheter 608 is configured to facilitate the positioning of a guttercatheter, as will be described below with respect to FIGS. 7a-c.

[0081]FIG. 6b is a schematic representation of delivery tube 604 andJ-catheter 608 positioned within a heart in accordance with anembodiment of the present invention. As shown, after delivery tube 604and J-catheter 608 are effectively “snaked” or inserted through afemoral artery, portions of delivery tube 604 and of J-catheter 608 arepositioned within an aorta 620 of a heart 616. A tip 626 of J-catheter608, which is substantially oriented at a right angle from the body ofJ-catheter 608, and an end of delivery tube 604 are oriented such thatthey pass through an aortic valve 630. Hence, an end of delivery tube604 and tip 626 are positioned at a top portion of left ventricle 624,where wall 632 of left ventricle 624 is relatively smooth. The relativesmoothness of the top portion of left ventricle 624 enables a catheterto be properly positioned within left ventricle 624 by guiding the tipof the catheter along wall 632. In one embodiment, tip 626 is orientedsuch that it is positioned approximately just below a mitral valve 628on the ventricular side of mitral valve 628.

[0082] Once positioned within left ventricle 624, J-catheter 608 may berotated within delivery tube 604 such that tip 626 is may enable agutter catheter fed therethrough to run along the contour of wall 632.Typically, the gutter catheter runs along the contour of wall 632 in anarea that is effectively defined between a plane associated withpapillary muscles 640, a plane associated with the posterior leaflet ofmitral valve 628, cordae tendonae 642, and wall 632. A “gutter” islocated in such an area or region and, more specifically, is positionedsubstantially right under mitral valve 628 where there is a relativelyinsignificant amount of trabeculae.

[0083] With reference to FIGS. 7a-7 c, a gutter catheter will bedescribed in accordance with an embodiment of the present invention. Agutter catheter 704, which is part of a catheter assembly 702 as shownin FIG. 7a, is arranged to be extended through J-catheter 626 such thatgutter catheter 704 may be steered within a left ventricle just beneatha mitral valve. Gutter catheter 704, which may include a balloon tip(not shown), is typically formed from a flexible material such as nylon,urethane, or PEBAX®. In one embodiment, gutter catheter 704, which issteerable, may be formed using a shape memory material.

[0084] As shown in FIGS. 7a and FIG. 7b, which represents a crosssection of catheter assembly 702 taken at a location 710, guttercatheter 704 is at least partially positioned within J-catheter 608which, in turn, is at least partially positioned within delivery tube604. Gutter catheter 704 may be free to rotate within and extend throughJ-catheter 608, while J-catheter 608 may be free to rotate within andextend through delivery tube 604.

[0085] Referring next to FIG. 7c, the positioning of gutter catheter 704within a left ventricle of the heart will be described in accordancewith an embodiment of the present invention. It should be appreciatedthat the representation of gutter catheter 704 within a left ventricle720 has not been drawn to scale, for ease of illustration and ease ofdiscussion. For instance, the distance between a wall 724 of leftventricle 720 and a mitral valve 728 has been exaggerated. In addition,it should also be appreciated that the positioning of delivery tube 604and, hence, J-catheter 608 and gutter catheter 704 within aortic valve732 may vary.

[0086] Gutter catheter 704 protrudes through tip 626 of J-catheter 608,and, through steering, essentially forms an arc shape similar to that ofmitral valve 728 along the contour of a wall 724 of left ventricle 720just beneath mitral valve 728, i.e., along the gutter of left ventricle720. Wall 724 of left ventricle 720 is relatively smooth just beneathmitral valve 728, i.e., generally does not include trabeculae. Hence,inserting catheter assembly 702 through an aortic valve 732 into anupper portion left ventricle 720 allows gutter catheter 704 to benavigated within left ventricle 720 along wall 724 substantially withoutbeing obstructed by trabeculae or cordae tendonae.

[0087] Gutter catheter 704 generally includes an opening or lumen (notshown) that is sized to accommodate a guide wire through which a guidewire may be inserted. The opening may be located along the central axisof gutter catheter 704, i.e., central axis 730 as shown in FIG. 7a.Delivering a guide wire through gutter catheter 704 enables the guidewire to effectively follow the contour of wall 724. In general, theguide wire may include an anchoring tip which enables the guide wire tobe substantially anchored against wall 724. FIG. 8 is a diagrammatictop-view cut-away representation of a left side of a heart in which aguide wire has been positioned in accordance with an embodiment of thepresent invention. It should be appreciated that the representation ofthe left side of a heart in FIG. 8 has not been drawn to scale, and thatvarious features have been exaggerated for ease of discussion. A guidewire 802 is positioned along wall 724 of left ventricle 720. Once guidewire 802 is inserted through gutter catheter 704 of FIGS. 7a-7 c, andanchored against wall 724 using an anchoring tip 806, gutter catheter704, along with J-catheter 708, are withdrawn from the body of thepatient. It should be appreciated that delivery tube 604 typicallyremains positioned within the aorta after guide wire 802 is anchored towall 724.

[0088] Guide wire 802, which may be formed from a material such asstainless steel or a shape memory material, is generally anchored suchthat guide wire 802 effectively passes along a large portion of wall724. Typically, guide wire 802 serves as a track over which a catheterthat carries plication structures may be positioned, i.e., a lumen of acatheter that delivers a plication element may pass over guide wire 802.Such a catheter may include a balloon structure (not shown), or anexpandable structure, that may facilitate the positioning of localplication structures by pushing the local plication structuressubstantially against the fibrous tissue around the mitral valve.

[0089] Forming local plications causes bunches of the fibrous tissuearound the mitral valve to be captured or gathered, thereby causingdilation of the anterior leaflet of the mitral valve to be reduced. Ingeneral, the local plications are discrete plications formed in thefibrous tissue around the mitral valve using suture structures ordiscrete mechanical elements. FIG. 9a is a representation of a top-downcut-away view of a left ventricle of the heart in which local plicationsuture structures have been implanted in accordance with an embodimentof the present invention. Suture structures, which include T-bars 904and threads 907, are implanted in tissue near a mitral valve 916, e.g.,an annulus of mitral valve 916. Typically, the tissue in which suturestructures are implanted is fibrous tissue 940 which is locatedsubstantially around mitral valve 916. Suitable suture structuresinclude, but are not limited to, structures which include T-bars 904 andthreads 907, as will be described below with reference to FIGS. 10a, 10b, 11, and 12 a-c.

[0090] Since T-bars 904 or similar structures, when implanted, may cutthrough tissue 940, pledgets 905 may against a ventricular side tissue940 to effectively “cushion” T-bars 904. Hence, portions of T-bars 904are positioned above mitral valve 916, i.e., on an atrial side of mitralvalve 916, while pledgets 905 are positioned on the ventricular side ofmitral valve 916. It should be appreciated that additional oralternative pledgets may be positioned on the atrial side of mitralvalve 916, substantially between tissue 940 and T-bars 904. Catheterswhich deliver suture structures 904 to an atrial side of mitral valve916 from a ventricular side of mitral valve 916 will be discussed belowwith respect to FIGS. 13a-c.

[0091] In the described embodiment, T-bars 904 are coupled such thatevery two T-bars, e.g., T-bars 904 a, is coupled by a thread, e.g.,thread 907 a. Thread 907 a is configured to enable T-bars 904 a to betensioned together and locked against tissue 940. Locking T-bars 904 aenables tissue 940 to be bunched or slightly gathered, therebyeffectively constraining the size, e.g., arc length, of mitral valve 916by reducing the an arc length associated with tissue 940. In otherwords, the presence of T-bars 904 which cooperate with thread 907 tofunction substantially as sutures, allows the size of a gap 908 betweenan anterior leaflet 920 and a posterior leaflet 918 to be reduced and,further, to be substantially prevented from increasing. As will beappreciated by those skilled in the art, over time, scar tissue (notshown) may form over pledgets 905 and T-bars 904.

[0092] Generally, the number of T-bars 904 used to locally bunch orgather tissue 940 may be widely varied. For instance, when substantiallyonly a small, localized regurgitant jet occurs in mitral valve 916, onlya small number of T-bars 904 may be implemented in proximity to theregurgitant jet. Alternatively, when the size of gap 908 is significant,and there is a relatively large amount of mitral valve leakage, then arelatively large number of T-bars 904 and, hence, pledgets 905 may beused to reduce the size of gap 908 by reducing the arc length of mitralvalve 916. Some pledgets 905 may be arranged to at least partiallyoverlap. To correct for a regurgitant jet that is centralized to onlyone section of mitral valve 916, T-bars 904 may be implemented asplicating elements near the regurgitant jet, and as reinforcing elementsaway from the regurgitant jet, e.g., to prevent progression of mitralvalve disease from causing a substantial gap to eventually form.

[0093] While the coupling of two T-bars 904 a with thread 907 a has beendescribed, it should be understood that the number of T-bars 904 coupledby a thread or threads 907 may vary. For example, if multiple T-bars 904are coupled by multiple threads 907, then it may be possible to gathermore fibrous tissue using fewer total T-bars 904. With reference to FIG.9b, the use of multiple T-bars 904 which are coupled by multiple threads907 will be described. T-bars 904 c are coupled by a thread 907 c, whileT-bars 904 d are coupled by a thread 907 c. Similarly, T-bars 904 e arecoupled by a thread 907 e. T-bar 904 d′ is further coupled by a thread907 f to T-bar 904 c″, and T-bars 904 d″ is also coupled by a thread 907g to T-bar 904 e′. As will be discussed below, threads 907 enable T-bars904 to be pulled against pledgets 905 and, hence, tissue 940. Suchcoupling of T-bars 904 enables plications in tissue 940 to be madebetween T-bars 904 c, between T-bars 904 d, and between T-bars 904 e,while allowing tissue to be at least somewhat gathered between T-bar 904c″ and T-bar 904 d′, and between T-bar 904 d″ and T-bar 904 e′.

[0094] In general, the configurations of suture structures which includeT-bars 904 and threads 907 may vary. One embodiment of a suitable suturestructure is shown in FIGS. 10a and 10 b. FIG. 10a and 10 b arerepresentations of a suture structure after T-bars have been introducedto an atrial side of fibrous tissue near a mitral valve in accordancewith an embodiment of the present invention. For purposes ofillustration, it should be understood that the elements and structuresrepresented in FIGS. 10a and 10 b, as well as substantially all otherfigures, have not been drawn to scale. A suture structure 1000 includesT-bars 904, or reinforcing elements, that are coupled to thread 907 suchthat when thread 907 is pulled, T-bars 904 effectively push againsttissue 940. As shown in FIG. 10b, pulling on thread 907 and pushing on alocking element 1002 causes locking element 1002 to contact aventricular side of tissue 940 and to effectively hold T-bars 904against tissue 940. Specifically, pulling on a loop 1004 of thread 907while pushing on locking element 1002 tightens T-bars 904 against tissue940 such that a plication 1006 may be formed in tissue 940 when lockingelement 1002 locks into position to lock T-bars 904 into place.

[0095] Pledgets 905, as will be appreciated by those skilled in the art,may serve as plication anchors for T-bars 904 which essentially functionas sutures. That is, pledgets 905 may prevent T-bars 904 from cuttingthrough tissue 940. In general, the configuration of pledgets 905 mayvary widely. For example, pledgets 905 may have a substantially tubularform, and may be formed from a material such as surgical, e.g., Dacron,mesh. However, it should be appreciated that pledgets 905 may be formedin substantially any shape and from substantially any material whichpromotes or supports the growth of scar tissue therethrough. Suitablematerials include, but are not limited to silk and substantially anybiocompatible porous or fibrous material.

[0096] Locking element 1002 may be a one-way locking element, e.g., anelement which may not be easily unlocked once it is locked, that isformed from a biocompatible polymer. The configuration of a lockingelement 1002 may be widely varied. Alternative configurations of lockingelement 1002 will be described below with respect to FIG. 11 and FIGS.12a-c. In order to engage locking element 1002 against pledgets 905, acatheter which is used to deliver T-bars 904 may be used to push lockingelement 1002 into a locked position. A catheter which delivers T-bars904 and may also be used to engage locking element 1002 will bediscussed below with reference to FIGS. 13a-c.

[0097] Like locking element 1002, T-bars 904 may also be formed from abiocompatible polymer. Thread 907, which may be coupled to T-bars 904through tying T-bars 904 to thread 907 or molding T-bars 904 over thread907, may be formed from substantially any material which is typicallyused to form sutures. Suitable materials include, but are not limitedto, silk, prolene, braided Dacron, and polytetrafluoroethylene (PTFE, orGoreTex).

[0098] As mentioned above, the configuration of locking element 1002 mayvary. For example, a locking element may include a spring element asshown in FIG. 11. A suture structure 1100 include T-bars 1104, a thread1107, and a locking element 1102. For ease of illustration, the elementsof suture structure 1100 have not been drawn to scale. Although suturestructure 1100 is not illustrated as including a pledget, it should beappreciated that suture structure 1100 may include a pledget or pledgetswhich serve as reinforcing elements which generally support the growthof scar tissue.

[0099] Locking element 1102 includes solid elements 1102 a and a springelement 1102 b. Although solid elements 1102 a maybe formed from abiocompatible polymer, solid elements 1102 a may also be formed frommaterial which is typically used to form pledgets. Spring element 1102 bis arranged to be held in an extended position, as shown, while a loop1114 in thread 1107 is pulled on. Once T-bars 1104 are in contact withtissue 1140, solid elements 1102 a may come into contact with tissue1140, and spring element 1102 b may contract to create a spring forcethat pulls solid elements 1102 a toward each other. In other words, onceT-bars 1104 are properly positioned against tissue 1140, locking element1102 may be locked to form a plication or local bunching of tissue 1140.

[0100] In one embodiment, the formation of scar tissue on the fibroustissue which is in proximity to a mitral valve may be promoted before aplication is formed, or before the fibrous tissue is gathered tocompensate for mitral valve insufficiency. With reference to FIGS.12a-c, a locking element which promotes the growth of scar tissue beforea plication is formed will be described in accordance with an embodimentof the present invention. As shown in FIG. 12a, a suture structure 1200,which is not drawn to scale, includes a locking element 1204, a thread1207, and T-bars 1204. Locking element 1204, which includes solidelements 1202 a, a spring element 1202 b, and a resorbable polymerovermold 1202 c formed over spring element 1202 b is coupled to thread1207 on a ventricular side of tissue 1240.

[0101] Overmold 1202 c, which may be formed from a resorbable lactidepolymer such as PURASORB, which is available from PURAC America ofLincolnshire, Ill., is formed over spring element 1202 b while springelement 1202 b is in an extended position. Overmold 1202 c is arrangedto remain intact while scar tissue 1250 forms over solid elements 1202a. In one embodiment, in order to facilitate the formation of scartissue, solid elements 1202 a may be formed from material that is porousor fibrous, e.g., “pledget material.”

[0102] Once scar tissue is formed over solid elements 1202 a, overmold1202 c breaks down, e.g., degrades, to expose spring element 1202 b, asshown in FIG. 12b. As will be understood by one of skill in the art, thechemical composition of overmold 1202 c may be tuned such that theamount of time that elapses before overmold 1202 c breaks down may becontrolled, e.g., controlled to break down after a desired amount ofscar tissue is expected to be formed. Hence, once overmold 1202 c breaksdown, and spring element 1202 b is allowed to contract, as shown in FIG.12c, enough scar tissue 1250 will generally have formed over solidelements 1202 a to effectively bond solid elements 1202 a against tissue1240 to allow for the formation of a relatively strong plication orgathering of tissue 1240.

[0103] While a loop 1214 of thread 1207 may be allowed to remainextended into a left ventricle of a heart, thread 1207 may be cut, i.e.,loop 1214 may be effectively removed, to reduce the amount of loosethread 1207 in the heart. Alternatively, loose thread 1207 mayeffectively be eliminated by gathering thread 1207 around a cylindricalarrangement (not shown) positioned over locking element 1202. That is, aspool or similar element may be included as a part of suture structure1200 to enable loose thread 1207 to either be gathered within the spoolor gathered around the exterior of the spool.

[0104] The use of overmold 1202 c enables anchoring forces which holdT-bars 1204 and locking element 1202 in position to be relatively low,as substantially no significant forces act on tissue 1240 until afterscar tissue or tissue in growth is created. Once scar tissue is created,and overmold 1202 c has degraded, then spring 1202 b compresses. Theanchoring forces generated at this time may be relatively high. However,as scar tissue has been created, the likelihood that T-bars 1204 cutinto tissue 1240 at this time is generally relatively low.

[0105] As mentioned above, catheters may be used to deliver suturestructures into a heart, and to engage the suture structures to tissuearound the mitral valve of the heart. One embodiment of a suturestructure delivery catheter which is suitable for use in acatheter-based annuloplasty that uses local plications will be describedwith respect to FIG. 13a. A delivery catheter 1300 may be positionedover a guide wire, e.g., guide wire 802 as shown in FIG. 8, which servesas a track to enable delivery catheter 1300 to be delivered in thegutter of a heart. It should be appreciated that the elements ofdelivery catheter 1302 have not been drawn to scale. Within deliverycatheter 1300 is a wire 1308 which carries T-bars 1304 of a suturestructure. In one embodiment, T-bars 1300 are coupled to a thread 1307and a locking element 1300 to form the suture structure. Typically, apointed or sharpened end 1311 of wire 1308 is configured to penetratetissue (not shown), e.g., fibrous tissue of the heart near a mitralvalve. Once end 1311 and T-bar 1304 are located above fibrous tissue,e.g., on an atrial side of a mitral valve, wire 1308 may be retracted arepositioned. After wire 1308 is repositioned, end 1311 may once againpenetrate tissue to effectively deposit T-bar 1304 over tissue on theatrial side of the mitral valve.

[0106] Wire 1308 or, more specifically, end 1311 maybe used to pullthread 1307 and to push locking element 1302 into position againsttissue near the mitral valve. By way of example, end 1311 may pull onthread 1307 until T-bars 1304 contact the tissue. Then, end 1311 may beused to lock locking element 1302 against the tissue and, as a result,create a plication in the tissue to effectively shrink the annulus ofthe mitral valve.

[0107] In order to create additional plications, wire 1308 and, in oneembodiment, delivery catheter 1300, may be retracted entirely out of apatient to enable additional T-bars to be loaded onto wire 1308. Onceadditional T-bars are positioned on wire 1308, wire 1308 may bereinserted into delivery catheter 1300, and delivery catheter 1300 maybe used to enable another plication to be created in the tissue which islocated near the mitral valve.

[0108]FIG. 13b is a representation of a second catheter which issuitable for delivering a suture structure in accordance with anembodiment of the present invention. A catheter 1340, which is not drawnto scale and which may include a lumen (not shown) that is arranged tobe inserted over a guide wire, includes two wires 1348 which arearranged to cooperate to carry a suture structure. As shown, wire 1348 acarries a T-bar 1344 a while wire 1348 b carries a T-bar 1344 b whichare coupled by a thread 1347 and, together with a locking element 1342,form a suture structure. Tips 1351 of wires 1348 pass through tissuenear a mitral valve to deposit T-bars 1344 above the mitral valve. OnceT-bars 1344 are deposited, tips 1351 maybe used to pull T-bars 1344against the tissue, as well as to lock locking element 1342 against anopposite side of the tissue. By way of example, tip 1351 b may beconfigured to pull on thread 1347 while tip 1351 a pushes againstlocking element 1342.

[0109] With reference to FIG. 13c, a catheter arrangement which maydeploy T-bars from its tip will be described in accordance with anembodiment of the present invention. A catheter arrangement 1360includes two catheters which each carry a T-bar 1364. It should beappreciated that the elements of FIG. 13c have not been drawn to scalefor ease of illustration. Specifically, catheter 1360 a carries T-bar1364 a at its tip, while catheter 1360 b carries T-bar 1364 b at itstip. A thread 1367 couples T-bars 1364 together such that a lockingelement 1362 through which thread 1367 passes may lock T-bars 1364substantially against tissue of a heart.

[0110] In one embodiment, catheter arrangement 1360 may require the useof two guide wires to guide each of catheter 1360 a and catheter 1360 binto the gutter of the heart. Alternatively, catheter 1360 a andcatheter 1360 b may be arranged such that both catheter 1360 a andcatheter 1360 b may be guided through the gutter of the heart throughthe use of a single guide wire.

[0111] Catheter 1360 a is configured to push T-bar 1364 a through tissuenear the mitral valve of the heart, and to release T-bar 1364 a onceT-bar 1364 a is located on an atrial side of the mitral valve.Similarly, catheter 1360 b is configured to push T-bar 1364 b throughthe tissue, and to release T-bar 1364 b. T-bars 1364 may be released,for example, when heat is applied to a dielectric associated withcatheters 1360 that causes T-bars 1364 to be effectively snapped off.Alternatively, a mechanical mechanism (not shown) that engages T-bars1364 to catheters 1360 maybe disengaged to release T-bars 1354. OnceT-bars 1364 are positioned on the atrial side of the mitral valve,catheter 1360 may be used to pull on thread 1367 and to push on lockingelement 1362.

[0112] With reference to FIGS. 14a and 14 b, the performance of anannuloplasty procedure using a catheter-based system which implantssuture structures in tissue near a mitral valve will be described inaccordance with an embodiment of the present invention. Once a patientis prepared, e.g., sedated, an annuloplasty procedure 1400 may beginwith the insertion of a delivery tube and a J-catheter into the leftventricle of the heart of the patient. The delivery tube and theJ-catheter may be inserted into the body of the patient through thefemoral artery, and threaded through the femoral artery and the aortainto the left ventricle of the heart. Generally, the J-catheter ispositioned within the delivery tube. One embodiment of the delivery tubeand a J-catheter were described above with respect to FIGS. 6a and 6 b.As will be appreciated by those skilled in the art, the delivery tubeand the J-catheter are typically each threaded through the aortic valveto reach the left ventricle.

[0113] Once the delivery tube and the J-catheter are positioned withinthe left ventricle, a gutter catheter may be extended through theJ-catheter in step 1408. As was discussed above with reference to FIGS.7a-c, the gutter catheter is arranged to effectively run against agutter of the wall of the left ventricle substantially immediately underthe mitral valve. Specifically, the gutter catheter may be positioned inthe space in the left ventricle between the mitral valve and the musculipapillares, or papillary muscles. The gutter catheter often has a tipthat is steerable and flexible. In one embodiment, the tip of the guttercatheter may be coupled to an inflatable balloon. The J-catheter serves,among other purposes, the purpose of allowing the gutter catheter to beinitially oriented in a proper direction such that the gutter cathetermay be positioned along the wall of the left ventricle.

[0114] In step 1412, a guide wire with an anchoring feature may bedelivered through the gutter catheter, e.g., through a lumen or openingin the gutter catheter. The guide wire is delivered through the guttercatheter such that it follows the contour of the gutter catheter againstthe wall of the left ventricle. After the guide wire is delivered, theanchoring feature of the guide wire is anchored on the wall of the leftventricle in step 1416. Anchoring the guide wire, or otherwiseimplanting the guide wire, on the wall of the left ventricle enables theguide wire to maintain its position within the left ventricle.

[0115] The J-catheter and the gutter catheter are pulled out of the leftventricle through the femoral artery in step 1420, leaving the guidewire anchored within the left ventricle, as was discussed above withrespect to FIG. 8. A T-bar assembly delivery catheter which carries aT-bar assembly is then inserted through the femoral artery into the leftventricle over the guide wire in step 1436. In one embodiment, the T-barassembly delivery catheter carries an uninflated balloon.

[0116] After the T-bar assembly delivery catheter is inserted into theleft ventricle, the balloon is inflated in step 1428. Inflating theballoon, e.g., an elastomeric balloon, at a relatively modest pressureusing, for example, an air supply coupled to the balloon through theT-bar assembly delivery catheter, serves to enable substantially anycatheter which uses the guide wire as a track to be pressed up againstthe fibrous tissue around the mitral valve. Generally, the inflatedballoon substantially occupies the space between the mitral valve andthe papillary muscles. In one embodiment, more than one balloon may beinflated in the left ventricle.

[0117] Once the balloon is inflated in step 1428. The T-bar assemblydelivery catheter effectively delivers T-bars, or similar mechanisms,pledgets, and thread which are arranged to attach or otherwise couplewith an annulus of the mitral valve, e.g., the fibrous tissue of theskeleton around the mitral valve, to create plications. Suitablecatheters were described above with respect to FIGS. 13a-c. In step1440, a plication is created using the T-bar assembly in substantiallyany suitable tissue near the mitral valve. For example, a plication maybe created by essentially forcing T-bars through the tissue, thenlocking the T-bars against the tissue using a locking mechanism of theT-bar assembly. Specifically, the plication or bunching of tissue may becreated by extending sharpened wires which carry elements such as T-barsthrough the tissue, then retracting the sharpened wires, and pulling theT-bars into place. Positioning the T-bars, and locking the lockingmechanism causes the tissue between the T-bars and the locking mechanismmay bunch together.

[0118] Once the plication is created in step 1440, the balloon isgenerally deflated in step 1442. The T-bar assembly delivery cathetermay then be removed through the femoral artery in step 1444. Adetermination is made in step 1448 after the T-bar assembly deliverycatheter is removed as to whether additional plications are to becreated. If it is determined that additional plications are to becreated, then process flow returns to step 1436 in which the T-barassembly delivery catheter, which carries a T-bar assembly or suturestructure, is reinserted into the femoral artery.

[0119] Alternatively, if it is determined in step 1448 that there are nomore plications to be created, then process flow proceeds to step 1456in which the guide wire may be removed. After the guide wire is removed,the delivery tube may be removed in step 1460. Once the delivery tube isremoved, the annuloplasty procedure is completed.

[0120] In lieu of using suture structures such as T-bar assemblies tocreate local plications, other elements may also be used to create localplications in fibrous tissue near the mitral valve during anannuloplasty procedure. FIG. 15 is a cut-away top view representation ofa left side of a heart in which local plications have been created usingindividual, discrete elements in accordance with an embodiment of thepresent invention. Local plication elements 1522 are effectivelyimplanted in fibrous tissue 1540 around portions of a mitral valve 1516in order to reduce the size of a gap 1508 between an anterior leaflet1520 and a posterior leaflet 1518, e.g., to reduce the arc lengthassociated with posterior leaflet 1518. Local plication elements 1522are arranged to gather sections of tissue 1540 to create localplications. The local plications created by local plication elements1522, which are generally mechanical elements, reduce the size of themitral valve annulus and, hence, reduce the size of gap 1508. As will beunderstood by those skilled in the art, over time, scar tissue may growaround or over local plication elements 1522.

[0121] The configuration of local plication elements 1522 may be widelyvaried. For example, local plication elements 1522 may be metallicelements which have spring-like characteristics, or deformable metallicelements which have shape memory characteristics. Alternatively, eachlocal plication element 1522 may be formed from separate pieces whichmay be physically locked together to form a plication. With reference toFIGS. 16a-d, one embodiment of a local plication element which hasspring-like characteristics will be described in accordance with anembodiment of the present invention. A local plication element 1622 maybe delivered to a ventricular side, or bottom side, of tissue 1640 whichis located near a mitral valve. When delivered, as for example through acatheter, element 1622 is in a substantially folded, closed orientation,as shown in FIG. 16a. In other words, element 1622 is in a closedconfiguration that facilitates the delivery of element 1622 through acatheter. After an initial compressive force is applied at corners 1607of element 1622, sides or tines 1609 of element 1622 may unfold or open.As tines 1609 open, tips 1606 of tines 1609 may be pressed againsttissue 1640, as shown in FIG. 16b. The application of compressive forceto tines 1609, as well as a pushing force to a bottom 1611 of element1622, allows tips 1606 and, hence, tines 1609 to grab tissue 1640 astips 1606 push through tissue 1640, as shown in FIG. 16c. The closing oftines 1609, due to compressive forces applied to tines 1609, causestissue 1640 to be gathered between tines 1609 and, as a result, causes aplication 1630 to be formed, as shown in FIG. 16d. In one embodiment,the catheter (not shown) that delivers element 1622 may be used to applyforces to element 1622.

[0122] As mentioned above, elements used to create local plications maybe created from shape memory materials. The use of a shape memorymaterial to create a plication element allows the plication element tobe self-locking. FIG. 17a is a representation of one plicafion elementwhich is formed from a shape memory material in accordance with anembodiment of the present invention. A clip 1704, which may be formedfrom a shape memory material, i.e., an alloy of nickel and titanium, isarranged to be in an expanded state or open state when it is introduced,e.g., by a catheter, into the gutter of the left ventricle. Typically,holding clip 1704 in an expanded state involves applying force to clip1704. In one embodiment, a catheter may hold sides 1708 of clip 1704 tomaintain clip 1704 in an expanded state.

[0123] Once tips 1706 of clip 1704 are pushed through the fibrous tissuenear the mitral valve of the heart such that tips 1706 are positioned onan atrial side of the mitral valve, force may be removed from clip 1704.Since clip 1704 is formed from a shape memory material, once force isremoved, clip 1704 forms itself into its “rest” state of shape, as shownin FIG. 17b. In its rest state or preferred state, clip 1704 is arrangedto gather tissue in an opening 1712 defined by clip 1704. That is, thedefault state of clip 1704 is a closed configuration which is effectiveto bunch tissue to create a local plication.

[0124] Another discrete self-locking plication element which is suitablefor creating a local plication is a clip which may twist from an openposition to a closed, or engaged position, once force applied to holdthe clip in an open position is removed. FIG. 18a is a representation ofanother self-locking plication element shown in a closed position inaccordance with an embodiment of the present invention. A clip element1800, which may be formed from a material such as stainless steel or ashape memory material, is preloaded such that once tissue 1830 ispositioned in a gap 1810 between a tine 1806 and a time 1808, clipelement 1800 may return to a state which causes tissue 1830 to bepinched within a gap or space 1810.

[0125] Tine 1806 and tine 1808 first pierce tissue 1830, e.g., thetissue of an annulus of a mitral valve. As tine 1806 and tine 1808 aredrawn together to create a plication, thereby reducing the size of gap1810 by reducing a distance 1820, a bottom portion 1812 of clip element1800 twists, as for example in a quarter turn, effectively by virtue ofshape memory characteristics of clip element 1800. Thus, an effectivelock that holds tine 1806 and tine 1808 in a closed position such thattissue 1830 is gathered to form a local plication results.

[0126] In lieu of a preloaded clip element, a clip element may include alock mechanism which engages when force is applied. FIG. 18a is arepresentation of a self-locking plication element which includes asliding lock in accordance with an embodiment of the present invention.A clip element 1850 includes a body 1852 and a slider 1862 which isarranged to slide over at least a portion of body 1852. Clip element1850, which may be formed from a material such as stainless steel or ashape memory alloy, includes a tip 1856 and a tip 1858 which aresubstantially separated by a gap 1856 when slider 1862 is in an unlockedposition. As shown, slider 1862 is in an unlocked or open position whenslider 1862 is positioned about a tapered neck 1854 of body 1852.

[0127] When clip element 1850 is delivered into a left ventricle, e.g.,using a catheter, clip element 1850 is positioned within the leftventricle such that tip 1856 and tip 1858 are effectively piercedthrough fibrous tissue 1880 near the mitral valve. After tip 1856 andtip 1858 are positioned substantially on an atrial side of tissue 1880,force may be applied to slider 1862 to move slider 1862 in a y-direction1870 b over body 1852. As slider moves in y-direction 1870 b away fromtapered neck 1854, slider 1862 forces tip 1856 and tip 1858 togetherclose gap 1860, i.e., tip 1856 and tip 1858 move towards each other inan x-direction 1870 a. When tip 1856 and tip 1858 cooperate to close gap1860, tissue 1880 is gathered within clip element 1850, thereby creatinga local plication.

[0128] In one embodiment, when slider 1862 is in a closed position suchthat tip 1856 and tip 1858 cooperate to close gap 1856, slider 1862 maycontact tissue 1880. Hence, in order to promote the growth of scartissue over parts of clip element 1850 or, more specifically, slider1862, at least a top surface of slider 1862 may be covered with apledget material, e.g., a mesh which supports the growth of scar tissuetherethrough.

[0129] Locking elements which create local plications may includeelements which have two or more substantially separate pieces which locktogether around tissue. An example of a locking element which includestwo separate pieces is shown in FIG. 19. As shown in FIG. 19, a lockingelement 2000 may include a receiver piece 2002 and a locker piece 2004,which may generally be formed from substantially any suitable material,as for example a biocompatible plastic material. Receiver piece 2002 andlocker piece 2004 each include a tine 2006. Tines 2006 are arranged topierce and to engage tissue to create a local plication.

[0130] A cable tie portion 2010 of locker piece 2004 is configured to bedrawn through an opening 2008 which engages cable tie portion 2010.Opening 2008 includes features (not shown) which allow cable tie portion2010 to be pulled through opening 2008 and locked into position, andwhich prevent cable tie portion 2010 substantially from being pushed outof opening 2008. Cable tie portion 2010 is locked in opening 2008 whenbevels 2012 come into contact and effectively force tines 2006 to clampdown. Once tines 2006 clamp down, and locker piece 2004 is lockedagainst receiver piece 2002, a local plication is formed.

[0131] The operation of locking element 2000 will be described withrespect to FIGS. 20a-d in accordance with an embodiment of the presentinvention. As shown in FIG. 20a, receiver piece 2002 and locker piece2004 may be delivered substantially beneath fibrous tissue 2050 near amitral valve (not shown). Receiver piece 2002 and locker piece 2004 maybe delivered using a catheter which includes a top surface 2054. Topsurface 2054 of the catheter is arranged to apply force to tines 2006such that tines 2006 remain in an effectively undeployed, e.g.,partially bent or folded, position while being delivered by thecatheter.

[0132] Once receiver piece 2002 and locker piece 2004 are positionedunder tissue 2050 near a location where a plication is to be formed,forces are applied to receiver piece 2002 and locker piece 2004 to pushreceiver piece 2002 and locker piece 2004 together and effectivelythrough an opening 2058 in top surface 2054 of the catheter, as shown inFIG. 20b. The forces are typically applied by mechanisms (not shown)associated with the catheter. As tines 2006 pass through opening 2058,tines 2006 “open,” or deploy in order to pierce tissue 2050.

[0133] After piercing tissue 2050, tines 2006 continue to penetrate andto gather tissue 2050 while receiver piece 2002 and locker piece 2004are pushed together. As receiver piece 2002 and locker piece 2004 arepushed together, cable tie portion 2010 is inserted into opening 2008(shown in FIG. 19) of receiver portion 2002, as shown in FIG. 20c. Cabletie portion 2010 eventually locks with respect to opening 2008 whenbevels 2012 come into contact. When bevels 2012 come into contact, tines2006 close inwards, causing tissue 2050 to be captured, i.e., causing alocal plication 2060 to be formed. Once a local plication is formed, andforce is no longer required to push receiver piece 2002 and locker piece2004 together, the catheter which delivered receiver piece 2002 andlocker piece 2004 may be removed from the left ventricle.

[0134] Referring next to FIGS. 21a and 21 b, an annuloplasty procedurewhich uses a catheter-based system to create local plications in tissuenear a mitral valve using discrete elements will be described inaccordance with an embodiment of the present invention. After a patientis prepared, an annuloplasty procedure 2100 may begin with the insertionof a delivery tube and a J-catheter into the left ventricle of the heartof the patient in step 2104. Once the delivery tube and the J-catheterare positioned within the left ventricle, a gutter catheter may beextended through the J-catheter in step 2108. The gutter catheter, asdescribed above, is arranged to effectively run against a gutter of thewall of the left ventricle, e.g., between the mitral valve and thepapillary muscles. The gutter catheter often has a tip that is steerableand flexible.

[0135] In step 2112, a guide wire with an anchoring feature may bedelivered through the gutter catheter, e.g., through a lumen or openingin the gutter catheter. The guide wire is delivered through the guttercatheter such that it follows the contour of the gutter catheter againstthe wall of the left ventricle. After the guide wire is delivered, theanchoring feature of the guide wire is anchored on the wall of the leftventricle in step 2116.

[0136] The J-catheter and the gutter catheter are pulled out of the leftventricle through the femoral artery in step 2120, leaving the guidewire anchored within the left ventricle, as was discussed above withrespect to FIG. 8. A plication element delivery catheter which carries aplication element and, in one embodiment, is arranged to engage theplication element to the fibrous tissue around the mitral valve isinserted through the femoral artery into the left ventricle over theguide wire in step 2132. The plication element delivery catheter, in thedescribed embodiment, is coupled to an uninflated balloon which isinflated in step 2134 to effectively allow the plication elementdelivery catheter to be positioned substantially directly under thefibrous tissue. Once the plication element delivery catheter ispositioned in the left ventricle, e.g., over the guide wire in thegutter of the left ventricle, and the balloon is inflated, the plicationelement delivered by the delivery catheter is engaged to the fibroustissue in step 2136. That is, the plication element is coupled to thefibrous tissue such that a local plication is formed in the fibroustissue.

[0137] After the local plication is created in step 2136 by engagingtissue using the plication element, the balloon is deflated in step2138. Upon deflating the balloon, the plication element deliverycatheter may be removed through the femoral artery in step 2140. Adetermination is then made in step 2142 as to whether additional localplications are to be created. That is, it is determined if otherplication elements are to be introduced into the left ventricle. If itis determined that additional local plications are to be created,process flow returns to step 2132 in which the plication elementdelivery catheter, which carries another plication element, isreinserted into the femoral artery.

[0138] Alternatively, if it is determined in step 2142 that there are nomore local plications to be created, then the indication is that asufficient number of local plications have already been created.Accordingly, the guide wire may be removed in step 2148, and thedelivery tube may be removed in step 2152. After the delivery tube isremoved, the annuloplasty procedure is completed.

[0139] Although only a few embodiments of the present invention havebeen described, it should be understood that the present invention maybe embodied in many other specific forms without departing from thespirit or the scope of the present invention. By way of example, methodsof introducing plication elements or suture structures into the leftventricle to correct for mitral valve leakage, or mitral valveinsufficiency, may be applied to introducing plication elements orsuture structures which correct for leakage in other valves. Forinstance, the above-described procedure may be adapted for use in repaira leaking valve associated with a right ventricle.

[0140] While creating local plications in fibrous tissue associated withthe mitral valve of the heart has generally been described, theplications may also be created in other types of tissue which are near,around, in proximity to, or include the mitral valve. Other tissues towhich an plications may be formed include tissues associated with themyocardium, or tissues associated with the wall of the left ventricle.In one embodiment, a plication may be substantially directly formed inthe leaflets of the mitral valve.

[0141] It should be understood that although a guide wire has beendescribed as including an anchoring tip to anchor the guide wire to awall of the left ventricle, a guide wire may be anchored with respect tothe left ventricle in substantially any suitable manner. By way ofexample, a guide wire may include an anchoring feature which is locatedaway from the tip of the guide wire. In addition, a guide wire may moregenerally be any suitable guiding element which is configured tofacilitate the positioning of an implant.

[0142] While access to the gutter of the left ventricle has beendescribed as being associated with a minimally invasive catheterannuloplasty procedure in which local plications are formed, it shouldbe understood that the gutter of the left ventricle may also beaccessed, e.g., for an annuloplasty procedure, as a part of a surgicalprocedure in which local plications are formed. For instance, the aortaof a heart may be accessed through an open chest surgical procedurebefore a catheter is inserted into the aorta to reach the leftventricle. Alternatively, suture structures or plications elements maybe introduced on a ventricular side of a mitral valve through aventricular wall which is accessed during an open chest surgicalprocedure.

[0143] Pledgets have been described as being used in conjunction with,or as a part of, suture structures to facilitate the growth of scartissue as a result of an annuloplasty procedure. It should beappreciated, however, that the use of pledgets is optional. In addition,although pledgets have generally not been described as being used withclip elements which create local plications, it should be understoodthat pledgets may also be implemented with respect to clip elements. Byway of example, a clip element which includes tines may be configuredsuch that the tines pierce through pledgets before engaging tissuewithout departing from the spirit or the scope of the present invention.

[0144] When a clip element has tines that are arranged to pierce througha pledget before engaging tissue, the pledget may be of a hollow,substantially cylindrical shape that enables the pledget be delivered toa left ventricle over a guide wire positioned in the gutter of the leftventricle. The clip element may then be delivered by a catheter throughthe pledget. A substantially cylindrically shaped, hollow pledget whichis to be used with a suture structure may also be delivered over a guidewire, and the suture structure may then be delivered through thepledget. Delivering the suture structure through the pledget may enablea loop of thread that remains after the suture structure is locked intoplace to remain substantially within the pledget.

[0145] The configuration of clip elements may generally vary widely.Specifically, the shape of clip elements, the size of clip elements, andthe materials from which the clip elements are formed may be widelyvaried. For instance, in addition to clip elements that are formed fromshape memory material, preloaded, or self-locking using mechanicalstructures, clip elements may also be formed from thermally expandablematerials. That is, a clip may be formed such that it is in an open orflat position when delivered into a left ventricle. Such a clip may havean outer or “bottom” element that has a relatively high coefficient ofthermal expansion, and an inner or “top” element that deforms under theload generated by the outer element when heat is applied to cause theouter element to bend. Such a clip, once bent or deformed through theapplication of heat, may pierce tissue. When more heat is applied, theclip may bend more such that tissue is engaged between ends or sides ofthe clip to create a local plication. In such a system, the innermaterial may be arranged to maintain its deformed shape once heat is nolonger applied, and the heat may be applied through a catheter.

[0146] Suture structures and plication elements have been described asbeing used to correct for mitral valve insufficiency. In general, suturestructures and plication elements may also be used to essentiallyprevent the onset of mitral valve insufficiency. That is, localplications may be created to effectively stem the progression of mitralvalve insuffiency be reinforcing the perimeter of the annulus around themitral valve.

[0147] While suture structures that include T-bars, thread, and lockingelements, and are delivered to a left ventricle using a catheter, may beused to form discrete plications in fibrous tissue around the mitralvalve, it should be appreciated that sutures may also be sewn into thefibrous tissue. For example, a catheter which is inserted into the leftventricle through the aorta may be configured to sew sutures into thefibrous tissue using mechanisms carried by the catheter. Such suturesthat are sewn into the fibrous tissue may be sewn in any conventionalorientation, e.g., in an arc along the perimeter of the posteriorleaflet of the mitral valve.

[0148] Suture structures that include T-bars have generally beendescribed as including two T-bars which are located at ends of a thread,with a locking element and pledgets located therebetween, as shown, forexample, in FIG. 10a. The configuration of suture structures, however,may vary widely. By way of example, a suture structure with two T-barsmay include one T-bar at one end of the thread and a second T-bar whichis located along the length of the thread such that pulling on a looseend of the thread pulls the two T-bars together. Alternatively, a suturestructure may include more than two T-bars.

[0149] In general, the use of a single element type to create localplications during an annuloplasty procedure has been described. Itshould be understood that in one embodiment, different element types maybe used in a single annuloplasty procedure. For instance, both clipelements and suture elements may be used to create plications during asingle annuloplasty procedure. Alternatively, different types of clipelements or different types of suture elements may be used during aparticular annuloplasty procedure.

[0150] The steps associated with performing a catheter-basedannuloplasty may be widely varied. Steps may generally be added,removed, reordered, and altered without departing from the spirit or thescope of the present invention. Therefore, the present examples are tobe considered as illustrative and not restrictive, and the invention isnot to be limited to the details given herein, but may be modifiedwithin the scope of the appended claims.

What is claimed is:
 1. A method for performing annuloplasty, the method comprising: accessing a left ventricle of a heart to provide a plication element to the left ventricle; and engaging the plication element to tissue near a mitral valve of the heart, wherein engaging the plication element includes causing the plication element to gather a portion of the tissue to create a plication.
 2. A method as recited in claim 1 wherein accessing the left ventricle of the heart to provide the plication element includes accessing the left ventricle of the heart with a catheter arrangement.
 3. A method as recited in claim 2 wherein accessing the left ventricle of the heart using the catheter arrangement includes inserting the catheter arrangement into the left ventricle between a plane defined by the mitral valve and a plane associated with papillary muscles of the heart.
 4. A method as recited in claim 2 wherein engaging the plication element to tissue near the mitral valve includes: piercing the tissue using the plication element, wherein piercing the tissue using the plication element causes a first portion of the plication element to be positioned on an atrial side of the mitral valve and a second portion of the plication element to be positioned on a ventricular side of the mitral valve.
 5. A method as recited in claim 4 wherein the catheter is configured to cause the first portion of the plication element to be positioned on the atrial side of the mitral valve.
 6. A method as recited in claim 1 wherein the plication element includes a first bar element and a second bar element, the first bar element and the second bar element being coupled to a thread, the thread further being coupled to a locking mechanism, and wherein engaging the plication element to tissue near the mitral valve includes: inserting the first bar element and the second bar element through the tissue to an atrial side of the mitral valve; and positioning the locking mechanism against the tissue on a ventricular side of the mitral valve, wherein positioning the locking mechanism against the tissue causes the plication to be formed substantially between the first bar element, the second bar element, and the locking mechanism.
 7. A method as recited in claim 6 wherein the locking mechanism includes a pledget.
 8. A method as recited in claim 6 wherein the locking mechanism includes a spring element, the spring element being arranged to cause the locking mechanism to engage, wherein when the locking mechanism engages, the first bar element and the second bar element are brought into contact with the tissue.
 9. A method as recited in claim 6 wherein accessing the left ventricle of the heart to provide the plication element includes accessing the left ventricle of the heart using a catheter arrangement, the catheter arrangement being configured to introduce the first bar element and the second bar element through the tissue to an atrial side of the mitral valve and to position the locking mechanism against the tissue on the ventricular side of the mitral valve.
 10. A method as recited in claim 1 wherein engaging the plication element to tissue near the mitral valve to cause the plication element to gather the portion of the tissue to create the plication includes gathering the portion of the tissue on a ventricular side of the mitral valve
 11. A method as recited in claim 1 wherein the plication element is one selected from the group consisting of a suture structure and a clip.
 12. A method for performing an annuloplasty, comprising: accessing tissue located near the mitral valve of a heart; and creating a first discrete plication in the tissue using a first plication element, the first discrete plication being positioned to cause an arc length of the mitral valve to be reduced.
 13. A method as recited in claim 12 wherein accessing the tissue includes accessing the tissue through a left ventricle of the heart
 14. A method as recited in claim 13 wherein the tissue is accessed through the left ventricle of the heart using a catheter.
 15. A method as recited in claim 14 further including providing the first plication element through the catheter.
 16. A method as recited in claim 15 wherein the catheter is configured to cause the first plication element to create the first discrete plication.
 17. A method as recited in claim 15 wherein creating the first discrete plication in the tissue using the first plication element includes creating the first discrete plication in the tissue using the first plication element and the catheter.
 18. A method as recited in claim 17 wherein the first plication element is a clip element, and creating the first discrete plication in the tissue using the first plication element and the catheter includes engaging the tissue using the clip element.
 19. A method as recited in claim 17 wherein the first plication element is a locking element, the locking element including a first piece and a second piece, and creating the first discrete plication in the tissue using the first plication element and the catheter includes: penetrating the tissue with a part of the first piece and a part of the second piece; and engaging the tissue between the first piece and the second piece of the locking element.
 20. A method as recited in claim 17 wherein the first plication element includes a plurality of bar pieces, a thread, and a lock, the bar pieces and the lock being coupled to the thread, and creating the first discrete plication in the tissue using the first plication element and the catheter includes: penetrating the tissue to position the bar pieces on an atrial side of the tissue; tensioning the thread to position the bar pieces against the atrial side of the tissue; locking the lock against a ventricular side of the tissue, wherein locking the lock against the ventricular side of the tissue causes the first discrete plication to be formed substantially between the bar pieces and the lock.
 21. A method as recited in claim 12 further including: creating a second discrete plication in the tissue using a second plication element, the second plication element being substantially separate from the first plication element.
 22. A system for use in an annuloplasty procedure, the system comprising: a catheter assembly configured for insertion through an aorta of the heart into a left ventricle of the heart to reach a region of the left ventricle substantially below the mitral valve; and a bendable member, wherein the bendable member is movable between a first position for insertion into a left ventricle through the catheter assembly and a second position, the bendable member being configured to create a plication in tissue located near a mitral valve when the bendable member is in the second position.
 23. A system according to claim 22 wherein the first position is a collapsed position and the second position is an extended position.
 24. A system according to claim 22 wherein the first position is an open position and the second position is a closed position.
 25. A system for use in an annuloplasty procedure, the system comprising: a catheter assembly configured for insertion through an aorta of the heart into a left ventricle of the heart to reach a region of the left ventricle substantially below the mitral valve; and a suture structure comprising a first bar member, a second bar member, a thread, and a locking element, the first bar member and the second bar member being coupled to the thread, the locking element being arranged to move over the thread, the catheter assembly being configured to cause the first bar member and the second bar member to penetrate tissue near the mitral valve, the catheter assembly further being configured to move the locking element over the thread into contact with the tissue on a ventricular side of the mitral valve, wherein a plication is created in the tissue substantially between the first bar member, the second bar member, and the locking element.
 26. A system for performing annuloplasty on a mitral valve of a heart, the system comprising: a catheter assembly configured for insertion through an aorta of the heart into a left ventricle of the heart to reach a region of the left ventricle substantially below the mitral valve; a guide element shaped for insertion into the catheter assembly, the guide element having an anchorable feature; and a plication element, the plication element being shaped for insertion over the guide element into the left ventricle substantially below the mitral valve, wherein the plication element is configured to gather tissue of the heart to create a plication in the tissue.
 27. A system according to claim 26 wherein the plication element is a suture element, the suture element being configured to create a suture in the tissue to create the plication.
 28. A system according to claim 26 wherein the plication element is a clip element, the clip element being configured to bunch the tissue to create the plication.
 29. A system according to claim 26 wherein the catheter assembly includes a delivery tube and a gutter catheter, the gutter catheter being positioned at least partially within the delivery tube, wherein a portion of the gutter catheter is configured to be positioned substantially within a region of the left ventricle defined between a plane associated with the papillary muscles of the left ventricle and a plane associated with the mitral valve.
 30. A system according to claim 29 wherein the guide element is shaped for insertion into a lumen of the gutter catheter.
 31. A system according to claim 28 wherein the catheter assembly includes a delivery tube and a gutter catheter, the gutter catheter being positioned at least partially within the delivery tube, wherein a portion of the gutter catheter is configured to be positioned substantially within a region of the left ventricle defined between a plane associated with the papillary muscles of the left ventricle, a plane associated with the mitral valve, cordae tendonae of the left ventricle, and a wall of the left ventricle.
 32. A method for performing annuloplasty on a mitral valve of a heart, the method comprising: inserting a first catheter assembly into a left ventricle through an aorta of the heart and an aortic valve of the heart; positioning a guide element along a wall of the left ventricle beneath the mitral valve using the first catheter assembly; positioning a plication element in the left ventricle beneath the mitral valve using a second catheter assembly and the guide element as a guide; and engaging the plication element with tissue near the mitral valve using the second catheter assembly, wherein engaging the plication element with the tissue near the mitral valve creates a plication in the tissue.
 33. A method as recited in claim 32 wherein the first catheter assembly includes a first catheter and a second catheter, the second catheter being located at least partially within the first catheter, the first catheter being arranged to facilitate the positioning of the second catheter along the wall of the left ventricle, and wherein positioning the guide element along the wall includes: inserting the guide element through the second catheter; and anchoring the guide element against the wall.
 34. A method as recited in claim 32 wherein initially positioning the plication element in the left ventricle beneath the mitral valve using the guide element includes: inserting at least one expandable element into the left ventricle; and expanding the expandable element, wherein expanding the expandable element positions the second catheter assembly generally against the tissue near the mitral valve.
 35. A method as recited in claim 32 wherein the plication element with the tissue near the mitral valve includes at least partially penetrating the tissue with the plication element to create the plication.
 36. A method for performing annuloplasty, the method comprising: inserting at least one plication element into a left ventricle of a heart; and engaging said at least one plication element to tissue near a mitral valve of the heart such that the plication element gathers a portion of the tissue to create a plication in the tissue near the mitral valve. 